/* gzwrite.c -- zlib functions for writing gzip files
 * Copyright (C) 2004-2019 Mark Adler
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

#include "gzguts.h"

/* Local functions */
local int gz_init OF((gz_statep));
local int gz_comp OF((gz_statep, int));
local int gz_zero OF((gz_statep, z_off64_t));
local z_size_t gz_write OF((gz_statep, voidpc, z_size_t));

/* Initialize state for writing a gzip file.  Mark initialization by setting
   state->size to non-zero.  Return -1 on a memory allocation failure, or 0 on
   success. */
local int gz_init(state)
gz_statep state;
{
  int ret;
  z_streamp strm = &(state->strm);

  /* allocate input buffer (double size for gzprintf) */
  state->in = (unsigned char*)malloc(state->want << 1);
  if (state->in == NULL) {
    gz_error(state, Z_MEM_ERROR, "out of memory");
    return -1;
  }

  /* only need output buffer and deflate state if compressing */
  if (!state->direct) {
    /* allocate output buffer */
    state->out = (unsigned char*)malloc(state->want);
    if (state->out == NULL) {
      free(state->in);
      gz_error(state, Z_MEM_ERROR, "out of memory");
      return -1;
    }

    /* allocate deflate memory, set up for gzip compression */
    strm->zalloc = Z_NULL;
    strm->zfree = Z_NULL;
    strm->opaque = Z_NULL;
    ret = deflateInit2(strm, state->level, Z_DEFLATED, MAX_WBITS + 16,
                       DEF_MEM_LEVEL, state->strategy);
    if (ret != Z_OK) {
      free(state->out);
      free(state->in);
      gz_error(state, Z_MEM_ERROR, "out of memory");
      return -1;
    }
    strm->next_in = NULL;
  }

  /* mark state as initialized */
  state->size = state->want;

  /* initialize write buffer if compressing */
  if (!state->direct) {
    strm->avail_out = state->size;
    strm->next_out = state->out;
    state->x.next = strm->next_out;
  }
  return 0;
}

/* Compress whatever is at avail_in and next_in and write to the output file.
   Return -1 if there is an error writing to the output file or if gz_init()
   fails to allocate memory, otherwise 0.  flush is assumed to be a valid
   deflate() flush value.  If flush is Z_FINISH, then the deflate() state is
   reset to start a new gzip stream.  If gz->direct is true, then simply write
   to the output file without compressing, and ignore flush. */
local int gz_comp(state, flush)
gz_statep state;
int flush;
{
  int ret, writ;
  unsigned have, put, max = ((unsigned)-1 >> 2) + 1;
  z_streamp strm = &(state->strm);

  /* allocate memory if this is the first time through */
  if (state->size == 0 && gz_init(state) == -1)
    return -1;

  /* write directly if requested */
  if (state->direct) {
    while (strm->avail_in) {
      put = strm->avail_in > max ? max : strm->avail_in;
      writ = write(state->fd, strm->next_in, put);
      if (writ < 0) {
        gz_error(state, Z_ERRNO, zstrerror());
        return -1;
      }
      strm->avail_in -= (unsigned)writ;
      strm->next_in += writ;
    }
    return 0;
  }

  /* check for a pending reset */
  if (state->reset) {
    /* don't start a new gzip member unless there is data to write */
    if (strm->avail_in == 0)
      return 0;
    deflateReset(strm);
    state->reset = 0;
  }

  /* run deflate() on provided input until it produces no more output */
  ret = Z_OK;
  do {
    /* write out current buffer contents if full, or if flushing, but if
       doing Z_FINISH then don't write until we get to Z_STREAM_END */
    if (strm->avail_out == 0 ||
        (flush != Z_NO_FLUSH && (flush != Z_FINISH || ret == Z_STREAM_END))) {
      while (strm->next_out > state->x.next) {
        put = strm->next_out - state->x.next > (int)max
                  ? max
                  : (unsigned)(strm->next_out - state->x.next);
        writ = write(state->fd, state->x.next, put);
        if (writ < 0) {
          gz_error(state, Z_ERRNO, zstrerror());
          return -1;
        }
        state->x.next += writ;
      }
      if (strm->avail_out == 0) {
        strm->avail_out = state->size;
        strm->next_out = state->out;
        state->x.next = state->out;
      }
    }

    /* compress */
    have = strm->avail_out;
    ret = deflate(strm, flush);
    if (ret == Z_STREAM_ERROR) {
      gz_error(state, Z_STREAM_ERROR, "internal error: deflate stream corrupt");
      return -1;
    }
    have -= strm->avail_out;
  } while (have);

  /* if that completed a deflate stream, allow another to start */
  if (flush == Z_FINISH)
    state->reset = 1;

  /* all done, no errors */
  return 0;
}

/* Compress len zeros to output.  Return -1 on a write error or memory
   allocation failure by gz_comp(), or 0 on success. */
local int gz_zero(state, len)
gz_statep state;
z_off64_t len;
{
  int first;
  unsigned n;
  z_streamp strm = &(state->strm);

  /* consume whatever's left in the input buffer */
  if (strm->avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
    return -1;

  /* compress len zeros (len guaranteed > 0) */
  first = 1;
  while (len) {
    n = GT_OFF(state->size) || (z_off64_t)state->size > len ? (unsigned)len
                                                            : state->size;
    if (first) {
      memset(state->in, 0, n);
      first = 0;
    }
    strm->avail_in = n;
    strm->next_in = state->in;
    state->x.pos += n;
    if (gz_comp(state, Z_NO_FLUSH) == -1)
      return -1;
    len -= n;
  }
  return 0;
}

/* Write len bytes from buf to file.  Return the number of bytes written.  If
   the returned value is less than len, then there was an error. */
local z_size_t gz_write(state, buf, len)
gz_statep state;
voidpc buf;
z_size_t len;
{
  z_size_t put = len;

  /* if len is zero, avoid unnecessary operations */
  if (len == 0)
    return 0;

  /* allocate memory if this is the first time through */
  if (state->size == 0 && gz_init(state) == -1)
    return 0;

  /* check for seek request */
  if (state->seek) {
    state->seek = 0;
    if (gz_zero(state, state->skip) == -1)
      return 0;
  }

  /* for small len, copy to input buffer, otherwise compress directly */
  if (len < state->size) {
    /* copy to input buffer, compress when full */
    do {
      unsigned have, copy;

      if (state->strm.avail_in == 0)
        state->strm.next_in = state->in;
      have =
          (unsigned)((state->strm.next_in + state->strm.avail_in) - state->in);
      copy = state->size - have;
      if (copy > len)
        copy = (unsigned)len;
      memcpy(state->in + have, buf, copy);
      state->strm.avail_in += copy;
      state->x.pos += copy;
      buf = (const char*)buf + copy;
      len -= copy;
      if (len && gz_comp(state, Z_NO_FLUSH) == -1)
        return 0;
    } while (len);
  } else {
    /* consume whatever's left in the input buffer */
    if (state->strm.avail_in && gz_comp(state, Z_NO_FLUSH) == -1)
      return 0;

    /* directly compress user buffer to file */
    state->strm.next_in = (z_const Bytef*)buf;
    do {
      unsigned n = (unsigned)-1;
      if (n > len)
        n = (unsigned)len;
      state->strm.avail_in = n;
      state->x.pos += n;
      if (gz_comp(state, Z_NO_FLUSH) == -1)
        return 0;
      len -= n;
    } while (len);
  }

  /* input was all buffered or compressed */
  return put;
}

/* -- see zlib.h -- */
int ZEXPORT gzwrite(file, buf, len)
gzFile file;
voidpc buf;
unsigned len;
{
  gz_statep state;

  /* get internal structure */
  if (file == NULL)
    return 0;
  state = (gz_statep)file;

  /* check that we're writing and that there's no error */
  if (state->mode != GZ_WRITE || state->err != Z_OK)
    return 0;

  /* since an int is returned, make sure len fits in one, otherwise return
     with an error (this avoids a flaw in the interface) */
  if ((int)len < 0) {
    gz_error(state, Z_DATA_ERROR, "requested length does not fit in int");
    return 0;
  }

  /* write len bytes from buf (the return value will fit in an int) */
  return (int)gz_write(state, buf, len);
}

/* -- see zlib.h -- */
z_size_t ZEXPORT gzfwrite(buf, size, nitems, file)
voidpc buf;
z_size_t size;
z_size_t nitems;
gzFile file;
{
  z_size_t len;
  gz_statep state;

  /* get internal structure */
  if (file == NULL)
    return 0;
  state = (gz_statep)file;

  /* check that we're writing and that there's no error */
  if (state->mode != GZ_WRITE || state->err != Z_OK)
    return 0;

  /* compute bytes to read -- error on overflow */
  len = nitems * size;
  if (size && len / size != nitems) {
    gz_error(state, Z_STREAM_ERROR, "request does not fit in a size_t");
    return 0;
  }

  /* write len bytes to buf, return the number of full items written */
  return len ? gz_write(state, buf, len) / size : 0;
}

/* -- see zlib.h -- */
int ZEXPORT gzputc(file, c)
gzFile file;
int c;
{
  unsigned have;
  unsigned char buf[1];
  gz_statep state;
  z_streamp strm;

  /* get internal structure */
  if (file == NULL)
    return -1;
  state = (gz_statep)file;
  strm = &(state->strm);

  /* check that we're writing and that there's no error */
  if (state->mode != GZ_WRITE || state->err != Z_OK)
    return -1;

  /* check for seek request */
  if (state->seek) {
    state->seek = 0;
    if (gz_zero(state, state->skip) == -1)
      return -1;
  }

  /* try writing to input buffer for speed (state->size == 0 if buffer not
     initialized) */
  if (state->size) {
    if (strm->avail_in == 0)
      strm->next_in = state->in;
    have = (unsigned)((strm->next_in + strm->avail_in) - state->in);
    if (have < state->size) {
      state->in[have] = (unsigned char)c;
      strm->avail_in++;
      state->x.pos++;
      return c & 0xff;
    }
  }

  /* no room in buffer or not initialized, use gz_write() */
  buf[0] = (unsigned char)c;
  if (gz_write(state, buf, 1) != 1)
    return -1;
  return c & 0xff;
}

/* -- see zlib.h -- */
int ZEXPORT gzputs(file, s)
gzFile file;
const char* s;
{
  z_size_t len, put;
  gz_statep state;

  /* get internal structure */
  if (file == NULL)
    return -1;
  state = (gz_statep)file;

  /* check that we're writing and that there's no error */
  if (state->mode != GZ_WRITE || state->err != Z_OK)
    return -1;

  /* write string */
  len = strlen(s);
  if ((int)len < 0 || (unsigned)len != len) {
    gz_error(state, Z_STREAM_ERROR, "string length does not fit in int");
    return -1;
  }
  put = gz_write(state, s, len);
  return put < len ? -1 : (int)len;
}

#if defined(STDC) || defined(Z_HAVE_STDARG_H)
#include <stdarg.h>

/* -- see zlib.h -- */
int ZEXPORTVA gzvprintf(gzFile file, const char* format, va_list va) {
  int len;
  unsigned left;
  char* next;
  gz_statep state;
  z_streamp strm;

  /* get internal structure */
  if (file == NULL)
    return Z_STREAM_ERROR;
  state = (gz_statep)file;
  strm = &(state->strm);

  /* check that we're writing and that there's no error */
  if (state->mode != GZ_WRITE || state->err != Z_OK)
    return Z_STREAM_ERROR;

  /* make sure we have some buffer space */
  if (state->size == 0 && gz_init(state) == -1)
    return state->err;

  /* check for seek request */
  if (state->seek) {
    state->seek = 0;
    if (gz_zero(state, state->skip) == -1)
      return state->err;
  }

  /* do the printf() into the input buffer, put length in len -- the input
     buffer is double-sized just for this function, so there is guaranteed to
     be state->size bytes available after the current contents */
  if (strm->avail_in == 0)
    strm->next_in = state->in;
  next = (char*)(state->in + (strm->next_in - state->in) + strm->avail_in);
  next[state->size - 1] = 0;
#ifdef NO_vsnprintf
#ifdef HAS_vsprintf_void
  (void)vsprintf(next, format, va);
  for (len = 0; len < state->size; len++)
    if (next[len] == 0)
      break;
#else
  len = vsprintf(next, format, va);
#endif
#else
#ifdef HAS_vsnprintf_void
  (void)vsnprintf(next, state->size, format, va);
  len = strlen(next);
#else
  len = vsnprintf(next, state->size, format, va);
#endif
#endif

  /* check that printf() results fit in buffer */
  if (len == 0 || (unsigned)len >= state->size || next[state->size - 1] != 0)
    return 0;

  /* update buffer and position, compress first half if past that */
  strm->avail_in += (unsigned)len;
  state->x.pos += len;
  if (strm->avail_in >= state->size) {
    left = strm->avail_in - state->size;
    strm->avail_in = state->size;
    if (gz_comp(state, Z_NO_FLUSH) == -1)
      return state->err;
    memmove(state->in, state->in + state->size, left);
    strm->next_in = state->in;
    strm->avail_in = left;
  }
  return len;
}

int ZEXPORTVA gzprintf(gzFile file, const char* format, ...) {
  va_list va;
  int ret;

  va_start(va, format);
  ret = gzvprintf(file, format, va);
  va_end(va);
  return ret;
}

#else /* !STDC && !Z_HAVE_STDARG_H */

/* -- see zlib.h -- */
int ZEXPORTVA gzprintf(file,
                       format,
                       a1,
                       a2,
                       a3,
                       a4,
                       a5,
                       a6,
                       a7,
                       a8,
                       a9,
                       a10,
                       a11,
                       a12,
                       a13,
                       a14,
                       a15,
                       a16,
                       a17,
                       a18,
                       a19,
                       a20)
gzFile file;
const char* format;
int a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15, a16, a17,
    a18, a19, a20;
{
  unsigned len, left;
  char* next;
  gz_statep state;
  z_streamp strm;

  /* get internal structure */
  if (file == NULL)
    return Z_STREAM_ERROR;
  state = (gz_statep)file;
  strm = &(state->strm);

  /* check that can really pass pointer in ints */
  if (sizeof(int) != sizeof(void*))
    return Z_STREAM_ERROR;

  /* check that we're writing and that there's no error */
  if (state->mode != GZ_WRITE || state->err != Z_OK)
    return Z_STREAM_ERROR;

  /* make sure we have some buffer space */
  if (state->size == 0 && gz_init(state) == -1)
    return state->error;

  /* check for seek request */
  if (state->seek) {
    state->seek = 0;
    if (gz_zero(state, state->skip) == -1)
      return state->error;
  }

  /* do the printf() into the input buffer, put length in len -- the input
     buffer is double-sized just for this function, so there is guaranteed to
     be state->size bytes available after the current contents */
  if (strm->avail_in == 0)
    strm->next_in = state->in;
  next = (char*)(strm->next_in + strm->avail_in);
  next[state->size - 1] = 0;
#ifdef NO_snprintf
#ifdef HAS_sprintf_void
  sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13,
          a14, a15, a16, a17, a18, a19, a20);
  for (len = 0; len < size; len++)
    if (next[len] == 0)
      break;
#else
  len = sprintf(next, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12,
                a13, a14, a15, a16, a17, a18, a19, a20);
#endif
#else
#ifdef HAS_snprintf_void
  snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10,
           a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
  len = strlen(next);
#else
  len = snprintf(next, state->size, format, a1, a2, a3, a4, a5, a6, a7, a8, a9,
                 a10, a11, a12, a13, a14, a15, a16, a17, a18, a19, a20);
#endif
#endif

  /* check that printf() results fit in buffer */
  if (len == 0 || len >= state->size || next[state->size - 1] != 0)
    return 0;

  /* update buffer and position, compress first half if past that */
  strm->avail_in += len;
  state->x.pos += len;
  if (strm->avail_in >= state->size) {
    left = strm->avail_in - state->size;
    strm->avail_in = state->size;
    if (gz_comp(state, Z_NO_FLUSH) == -1)
      return state->err;
    memmove(state->in, state->in + state->size, left);
    strm->next_in = state->in;
    strm->avail_in = left;
  }
  return (int)len;
}

#endif

/* -- see zlib.h -- */
int ZEXPORT gzflush(file, flush)
gzFile file;
int flush;
{
  gz_statep state;

  /* get internal structure */
  if (file == NULL)
    return Z_STREAM_ERROR;
  state = (gz_statep)file;

  /* check that we're writing and that there's no error */
  if (state->mode != GZ_WRITE || state->err != Z_OK)
    return Z_STREAM_ERROR;

  /* check flush parameter */
  if (flush < 0 || flush > Z_FINISH)
    return Z_STREAM_ERROR;

  /* check for seek request */
  if (state->seek) {
    state->seek = 0;
    if (gz_zero(state, state->skip) == -1)
      return state->err;
  }

  /* compress remaining data with requested flush */
  (void)gz_comp(state, flush);
  return state->err;
}

/* -- see zlib.h -- */
int ZEXPORT gzsetparams(file, level, strategy)
gzFile file;
int level;
int strategy;
{
  gz_statep state;
  z_streamp strm;

  /* get internal structure */
  if (file == NULL)
    return Z_STREAM_ERROR;
  state = (gz_statep)file;
  strm = &(state->strm);

  /* check that we're writing and that there's no error */
  if (state->mode != GZ_WRITE || state->err != Z_OK)
    return Z_STREAM_ERROR;

  /* if no change is requested, then do nothing */
  if (level == state->level && strategy == state->strategy)
    return Z_OK;

  /* check for seek request */
  if (state->seek) {
    state->seek = 0;
    if (gz_zero(state, state->skip) == -1)
      return state->err;
  }

  /* change compression parameters for subsequent input */
  if (state->size) {
    /* flush previous input with previous parameters before changing */
    if (strm->avail_in && gz_comp(state, Z_BLOCK) == -1)
      return state->err;
    deflateParams(strm, level, strategy);
  }
  state->level = level;
  state->strategy = strategy;
  return Z_OK;
}

/* -- see zlib.h -- */
int ZEXPORT gzclose_w(file)
gzFile file;
{
  printk("gzclose_w\n");
  int ret = Z_OK;
  gz_statep state;

  /* get internal structure */
  if (file == NULL)
    return Z_STREAM_ERROR;
  state = (gz_statep)file;

  /* check that we're writing */
  if (state->mode != GZ_WRITE)
    return Z_STREAM_ERROR;

  /* check for seek request */
  if (state->seek) {
    printk("1.1\n");
    state->seek = 0;
    if (gz_zero(state, state->skip) == -1) {
      printk("1.0\n");
      ret = state->err;
    }
    printk("1.2\n");
  }
  printk("1\n");
  /* flush, free memory, and close file */
  if (gz_comp(state, Z_FINISH) == -1) {
    printk("2.0\n");
    ret = state->err;
  }
  if (state->size) {
    if (!state->direct) {
      (void)deflateEnd(&(state->strm));
      free(state->out);
    }
    free(state->in);
  }
  gz_error(state, Z_OK, NULL);
  free(state->path);
  printk("3\n");
  if (close(state->fd) == -1) {
    ret = Z_ERRNO;
  }
  free(state);
  printk("DONE\n");
  return ret;
}
